Dietary Supplements – Part I: The Prevalence Of Dietary Supplement Use Among U.S. Population

The daily use of dietary supplements has evolved in an exponential fashion that few would have predicted when Dr. Royal Lee founded Standard Process in 1929 and began the commercial sale of dietary supplements. Today, the dietary supplement industry is a multi-billion dollar annual business with tens of millions of Americans taking dietary supplements on a daily basis.

This article focuses on the prevalence of dietary supplement use in the United States. The findings from a National Center for Health Statistics (NCHS) report covering three time periods (i.e., 1988-1994, 1990-2000 and 2002-2006) of National Health and Nutrition Examination Survey (NHANES) data and a Council for Responsible Nutrition survey will be relied upon.

Upcoming articles will address myths and misconceptions associated with dietary supplements, why it is important to take dietary supplements, how or in what ways dietary supplements contribute to health, wellness and wellbeing and guidelines for taking dietary supplements, among other important issues related to the use, manufacture, sale and regulation of dietary supplements.

What Is A Dietary Supplement?

So as not to add to the already confusing and sometimes controversial conversation on dietary supplements, it is important for consumers to have a clear and concise description of what exactly a dietary supplement is and is not. As it is defined by the U.S. Congress in the 1994 Dietary Supplement Health and Education Act (DSHEA), a dietary supplement is a product (other than tobacco) that:

is intended to supplement the diet;

contains one or more dietary ingredients (including vitamins; minerals; herbs or other botanicals; amino acids; and other substances) or their constituents;

is intended to be taken by mouth as a pill, capsule, tablet, or liquid; and

is labeled on the front panel as being a dietary supplement (Dietary Supplement Health and Education Act of 1994, 1994).

It is important to remember that dietary supplements as described and defined in DSHEA are considered a category of food. They are deemed to be products intended to supplement a person’s day-to-day diet. According to the Food and Drug Administration (FDA), dietary supplements are not drugs. Hence, they are subject to different regulations than drugs are not intended to treat, diagnose, mitigate, prevent, or cure any disease (see U.S. Food and Drug Administration, 2015; National Institutes of Health, 2011).

Overall Prevalence of Dietary Supplement Use

In their report for the National Center for Health Statistics (NCHS) covering three time periods (i.e., 1988-1994, 1990-2000 and 2002-2006) of National Health and Nutrition Examination Survey (NHANES) data, Gahche et al. (2011) indicate that the use of dietary supplement is widespread among U.S. adults 20 years of age and older. Compared to the 42% of the U.S. population who used at least one dietary supplement 1988–1994, 53% of the population in 2003–2006 consumed at least one dietary supplement.

However, dietary supplement use proved to be more prevalent in a study for the Council for Responsible Nutrition (CRN), a trade association of the dietary supplement industry. The CRN contracted with Ipsos Public Affairs to conduct consumer surveys annually since 2000. Since 2007, the surveys were conducted online to approximately 2000 respondents annually. The actual CRN study included five years of data collected from 2007-2011 focusing on the prevalence of dietary supplement use among 2, 010 U.S. adults 18 years of age and older.

In the CRN study, Dickinson et al. (2014) reported that between 2007 and 2011 the overall use of dietary supplements among the respondents ranged from 64% to 69%, while the “regular” use of dietary supplements ranged from 48% to 53%. It worth noting that the regular use of dietary supplements in the CRN study reflected usage levels similar to the overall prevalence reported by Gahche et al. (2011) using NHANES data discussed above.

In a review of the health habits and other characteristics of dietary supplement users, Dickinson and McKay (2014) contend that NHANES data reflect respondents’ use of dietary supplements over a 30 day period, thereby, failing to include seasonal and occasional supplement users resulting in an underestimation of overall supplement use. In contrast, Dickinson and McKay (2014) assert that the CRN/Ipsos data include regular, occasional and seasonal use of dietary supplements throughout the year, giving a more realistic picture of the prevalence of dietary supplement use.

Conclusion

Taken together, the data from NHANES and the CRN showed that the overall use of dietary supplements ranged from 53% to 69%, with the regular use of dietary supplements ranging from 48% to 53%. Clearly, taking dietary supplements has become integrated into the food culture in the United States to the extent that 85% of adults express confidence in the safety, quality and effectiveness of dietary supplements (see Dickinson et al., 2014).

The high level of consumer confidence begs the question of how that confidence was created. Did it emerge from marketing efforts, health talk shows on television or radio, self-education or actual use or some combination thereof? Further, what is the health status and health habits of supplement users compared to nonusers? Psychologically speaking, what are supplement and non-supplement users’ attitudes, values and beliefs about dietary supplements? How consistent are people in their use of dietary supplements? Which supplements do people tend to take and why? How does the longevity and quality of life of supplements users compare to non-supplement users? These are some of the questions that will be addressed in upcoming articles in the series on dietary supplements.

Dickinson, A. Blatman, J., El-Dash, N. & Franco, J.C. (2014). Consumer Usage and Reasons for Using Dietary Supplements: Report of a Series of Surveys. Journal of the American College of Nutrition, 33 (2), 176-182.